Fold mountains

Iranian mountains: a great place to see plants you have never seen before

TEHRAN – Iran is a mountainous country sheltering an extraordinary vascular flora including many rare and endemic plant species of the alpine zone. The importance of mountain biodiversity to all of humanity triggers the changes in attitude and behavior necessary to secure mountain biodiversity and its genetic resources for future generations.

Mountain environments cover about 12 percent of the world’s land surface and directly support the 22 percent of the world’s population who live in mountainous regions and their immediate foreland. Mountain biodiversity provides basic ecosystem services such as freshwater, timber, medicinal plants and recreation for the surrounding plains and their increasingly urbanized areas, according to the report “mountain biodiversity and global change” published by FAO in 2010.

By preventing erosion, the plant diversity of the mountains guarantees the means of subsistence, the circulation routes and the quality of the watersheds. Over 50 percent of humanity benefits from the mountains as the world’s water towers. They are home to some of the most complex agro-cultural gene pools and traditional management practices in the world.

Based on the total area of ​​mountainous land alone, a conservative estimate of mountain plant species in the world is 50,000 species of flowering plants (out of a total of about 260,000). Considering the inclusion of tropical lowland mountains in the above definition, the number may well be twice as high.

On average, a single mountain system like the Alps, Pyrenees, Scandes or New Zealand Alps is home to a few hundred (often 500-600) different species in the Alpine Belt alone. There are no such estimates available for animals, invertebrates (eg, insects) in particular, but a common estimate for temperate to cool climates is 10 times the diversity of animal species than plants.

Iranian mountains among a unique world heritage

Referring to the rich biodiversity and unique characteristics of mountains around the world, the report calls Iran a great place to see plants you have never seen before; according to which, more than 100 mountain peaks are in Iran, some in the Zagros and Alborz mountains which reach altitudes of more than 4000 m.

The upper limit of vascular plants is 4800m, the highest point where a plant has been found in Iran. A first evaluation of the vascular flora shows that 682 species belonging to 193 genera and 39 families are known from the alpine zone. This zone is characterized by numerous species of hemicryptophytes and thorny cushions; the number of species decreases sharply as the altitude increases. The mountain flora of Iran is exceptional.

The Iranian mountains are located between Anatolia / Caucasus and the Hindu Kush; their flora contains elements from both regions. However, over 50 percent of these species are endemic to Iran (they do not exist anywhere else) and some are notable relict species, mostly local endemics with a narrow ecological range. These plants require careful management of conservation and protection, not only because they are rare but because the ecosystems in which they live are fragile, often very small, small and isolated in high altitude areas.

These cold-adapted plants are particularly vulnerable to the impacts of climate change, and intensive grazing over large parts of the Iranian mountains is expected to put additional pressure on them. Many of these plants are potentially threatened and vulnerable species, and their threat status must be assessed according to the criteria of the International Union for the Conservation of Nature (IUCN).

Land use change among the most dangerous incidents

The report goes on to identify the most dangerous incidents that seriously affect mountain biodiversity, including natural disasters, forest fires, overgrazing and the most destructive man-made changes in land use.

Natural disasters in the form of landslides, floods and avalanches hit mountains every year, affecting only small areas but also the diversity of habitats and the dynamics of ecosystems. These natural disturbances lead to surprisingly rapid natural regeneration of plants. On the other hand, the human impact dominates large areas and its effect is often irreversible. The effects of land use change can be more dramatic than natural disasters or climate change.

Impact of climate change on diversity

Then, he underlines that climate change can have disastrous consequences on the diversity of mountains, in particular an increase in atmospheric concentrations of greenhouse gases, the progressively earlier start of spring activities, the migration of plant and animal species, even extinction.

Global warming threatens mountain biodiversity by forcing living areas to move up the slopes, reducing the land area higher for organisms specifically adapted to the cold. With higher temperatures forecast, longer summers with greater incidence of drought are expected in many mountainous regions around the world. Although the effects vary by region and the magnitude of the increase in temperatures is debated, it is clear that the Earth has experienced exceptional warming over the past century, a warming that cannot be explained by natural factors. .

Climate change is linked to an increase in atmospheric concentrations of greenhouse gases (carbon dioxide CO2, methane CH4, nitrous oxide N2O, halocarbons) caused by human activities.

Greenhouse gases affect the absorption, scattering and emission of radiation into the atmosphere and at the Earth’s surface (IPCC 2007). Studies show that temperatures are very likely to increase further in the 21st century.

The rise in temperatures is associated with a decrease in the area of ​​mountain glaciers, a shorter duration of snow cover at altitudes below the treeline in temperate and boreal latitudes, and an increase in annual precipitation with a seasonality otherwise changing, that is to say without excluding periodic droughts in summer.

Many small glaciers are expected to disappear, while the volume of large glaciers will be reduced by 30-70% by 2050, resulting in reductions in flow in spring and summer.

Additionally, global warming since the 1960s has led to a progressively earlier onset of spring activities below the treeline. Above the treeline, increased precipitation associated with warming can increase snowpack in some areas and even delay spring.

Plants exhibit earlier budding or flowering, while increasing temperatures have altered the timing of hibernation, animal reproduction, and in some cases predator dependence on traditional prey. The effects of climate change on one species are likely to affect a cascade of other species in the food web.

Another widely observed phenomenon linked to global warming is the migration of plant and animal species. In the northern hemisphere, a northward movement of bird and butterfly species has been observed, as well as migration to higher altitudes. The size of cool habitats, however, will decrease dramatically, leaving less space for more species.

Protect precious mountain ecosystems

Managing mountain biodiversity is increasingly recognized as a global responsibility. Over the past 40 years, protected areas have grown six to eight times, mainly in mountain areas, from 9 percent of the total mountain area in 1997 to 16 percent in 2010.

While protected areas are essential, they alone cannot ensure the conservation of biodiversity or cultural heritage. Traditional indigenous communities often use and manage biodiversity in mountainous protected areas and perhaps even more threatened than biodiversity itself.

The mountain regions where people live and work require innovative and respectful approaches to conservation; local people should be encouraged to manage their natural and cultural heritage. The participation of mountain communities at all stages is crucial in the sustainable management and use of biodiversity.

A gradual paradigm shift in conservation policies and practices has included the acceptance of communities as an integral part of national conservation initiatives and the integration of many global conventions.

Mountain land users can also be compensated for the lack of local benefits through payment for environmental services.


Source link